New chromosome number inRutaceae

Detailed chromosome counts have been made in 61 species, belonging to 33 genera ofRutaceae. 30 of these species are reported here for the first time. For 18 species at least one previous publication gives a chromosome number differing from that reported here. Such discrepancies are, in most cases, due to errors in counting or identification of the material. By critically reviewing the literature on each particular case, it appears possible to eliminate most of the false data. On the basis of the present results, the base number x = 10 is proposed for the genusRuta.Cytogenetics ofRutaceae, I.